Guest - Not logged in 

Reviews > Water Treatment > Ultraviolet > SteriPEN Classic 3 > Test Report by Mike Curry

February 03, 2015



NAME: Mike Curry
EMAIL: thefishguy hotmail com
AGE: 44
LOCATION: Aberdeen, WA
HEIGHT: 5' 11" (1.80 m)
WEIGHT: 190 lb (86.20 kg)

I've been backpacking, climbing, ski-packing, bushwhacking, and snowshoeing throughout the mountains of Oregon and Washington for over 25 years. I'm an all-season, all terrain, off-trail kind of guy, and enjoy everything from casual hikes with my children to mountaineering and alpine rock climbing in the Pacific Northwest. While I've carried packs (with winter climbing gear) in excess of 70 pounds (32 kilos), the older I get the more minimalist I become.



Manufacturer: Hydro-Photon, Inc.
Photo courtesy of manufacturer

Year of Manufacture: 2014
Manufacturer's Website:
MSRP: US $69.95
Listed Weight: 2.9 oz (82 g)
Measured Weight: 3.0 oz (85 g) (including lamp cover)
Pre filter measured weight: 1.5 oz (43 g)
Protective case weight: 0.9 oz (25 g)

Other details:
Dimensions 7.3 x 1.7 x 1.7 in (185 x 43 x 43 mm)
4 AA batteries required
Minimum bottle opening size: .08 in (22mm)


The SteriPEN Classic 3 appears to be a very refined product in every way. Its retail packaging, instructions, the manner in which the packaging contents are arranged, the device and accessories, all appeared so very well designed and thought out I found it very confidence-inspiring. That was my first impression upon opening the package.

The SteriPEN itself almost looks to me like a small medical device. It is very simple: a "handle" area with a battery door on the end, a power button, and three small LED indicators (two green, one red). Pulling off the plastic cover reveals the lamp, with two metal water sensor pins at the base. Very simple, very refined.

The pre-filter is a separate device for water that may have debris or other items that can be easily filtered out. It consists of a filter adapter that screws onto a large-mouth water bottle, and a filter that inserts into a small hole in the middle of it. Once this is all attached, the bottle is filled by pouring water through the filter or by submersion. Once the bottle is full, the filter can be removed, and the SteriPEN can be inserted into the hole, forming a watertight seal. The bottle can then be inverted for purification.

There is also a black fabric case that fits the SteriPEN nicely, and includes a hook-and-loop belt loop to attach to a belt or packstrap.

Overall, my initial impressions were very positive.


The SteriPEN Classic 3 came with what I consider to be some of the best-written instructions I've ever encountered for any kind of product. First I opened the simple three-step instructions (with high quality line drawings) that appear upon opening the first fold in the leaflet. This simple section describes basic use in a way that I felt confident I could use the device without further instruction. Opening the instruction leaflet all the way revealed comprehensive instructions on use, battery type recommendations, care and cleaning, interpreting the LED indicator light patterns, tips for safe use, frequently asked questions, pre-filter use, and some legal disclaimers. The instructions were well organized, easy to follow, easy to understand, and included excellent line drawings and diagrams to support the text.

In addition to the main instructions, when I opened the battery cover, I found a insert in the battery compartment that further clarified battery recommendations (lithium disposable or nickel metal hydride rechargeable are preferred over alkaline due to alkaline batteries not providing as many purification cycles, though alkaline do work). The insert also clarified with a line drawing how to insert the batteries and lock the battery door, all of which is well-labeled on the device and which I found very intuitive.


While I didn't have any of the preferred batteries available when the SteriPEN Classic 3 arrived, I was able to scrounge up 4 alkaline batteries for a quick test. Pressing the power button twice, both green LED indicators lit up, as they should (pressing once will purify 1/2 L and light one indictor, twice purifies 1 L and lights both indicators). When the indicators started flashing, I submerged the UV lamp in my water bottle until the water sensor pins were submerged, and the UV Indicator lamp lit up (indicating purification was in process). After a short time, the UV indicator lamp turned off, and the LED indicator light flashed green to let me know the process was successful.

In the end, I found it to be a very simple and intuitive process.

Using the pre-filter was less intuitive, but the instructions described it clearly. I attached the screw-on pre-filter adapter to a water bottle, and twisted in the filter screen. I filled the bottle by submerging it in a sink of water, which took a little time but no real effort. I then removed the bottle from the water, twisted off the pre-filter, and inserted the activated SteriPEN in the hole in the pre-filter adapter, which sealed nicely. I inverted the bottle as the instruction indicated, and waited for the light to go off. Afterward, I turned it back over, removed the SteriPEN and adapter, and put it all away.

Last of all, inserting the SteriPEN into its soft case, I found it fit snugly but well. The case, however, does not hold the pre-filter or adapter.

Overall, I found it all pretty easy to use.


The SteriPEN Classic 3 appears to be a very well-designed and constructed water purification device, feature-rich yet simple to operate, and I look very forward to using it in the field.



My daughter demonstrates using the adapter
I have used the SteriPEN Classic 3 on 4 nights of overnight use (8 days - all weekend trips) and multiple day hikes in the Olympic Mountains and Mt. Rainier National Park in Washington state. Water has been gathered primarily from streams, but I've also gathered water from ponds on two occasions.

The water treated has generally been clear, on one occasion suspended sediment in the water rendered it somewhat opaque (I was able to make out my finger while looking through the water in a dark 1L bottle, but barely). I would estimate water temperatures in range of 35-45 F (2-7 C), though this is purely speculation on my part.



So far the SteriPEN Classic 3 has not given me any problems. It has worked effectively as designed, and I haven't gotten sick. (Disclaimer: lacking water tests, absence of illness isn't necessarily proof of the tool's effectiveness; other possibilities are that the water was already uncontaminated or that I didn't react to any existing pathogens.)


I have to say I really, really like this device so far. I have always purified water in a full 1L bottle, so I push the power button twice (confirmed by both lights going solid green), remove the protective cover, and stick it in the water until the contacts touch and the light comes on. Stir or swirl until the lights go off. Simple, which is just the way I like things.

I must admit I was skeptical about the pre-filter. At first it seemed hard to attach and detach the screen part (so that the SteriPEN could be inserted into the hole it goes in to allow the bottle to be inverted, as shown in one of my pictures). Over time, attaching and detaching the screen part became easy, as the components seemed to wear or mold better to one another. I also thought I would be unlikely to bring the pre-filter, as my water sources are usually fairly clear, but I've found it serves another important function. When using the pre-filter adapter, I can invert my water bottle during the process. The advantage this has is that the contacts stay in the water. When simply submerging the SteriPEN in the water and stirring, I have to pay attention and not accidentally lift the SteriPEN, because if the contacts aren't touching water, it turns off, and I get to start over.
"So easy even a dad can do it!"

The pre-filter does a pretty good job of filtering larger debris. Think: "the stuff that might get stuck in my teeth." It didn't seem to filter much of the suspended sediment out of the water. That wasn't a problem, though, as the device worked fine, and the pre-filter adapter was worth carrying for the reason noted above.

Would I carry the pre-filter and adapter on most trips? Probably not, but It's small enough and light enough that I certainly might throw it in when light and compact weren't major factors.

While I probably wouldn't carry the case on most trips, it does work well. The protective cover, on the other hand, I keep on the device except when it's in use, as it gives me some piece of mind. The battery door is pretty easy to open and close, though I had to be careful about lining up the arrow with the lock/unlock symbol when it was dark (although it appears it won't let me connect it incorrectly).


My first efforts with the SteriPEN Classic 3 were using fresh alkaline batteries. I may have lost count, but I know that I had purified at least 25 L when the replace battery light came on, and I treated 4 more liters before I actually replaced the batteries.

I have since replaced the original Alkaline with Lithium batteries, and have not yet exhausted my first set of batteries.


The SteriPEN Classic 3 has performed well so far. It's been easy to use, and I haven't gotten sick, so I presume it is doing its job. (Disclaimer: lacking water tests, absence of illness isn't necessarily proof of the tool's effectiveness; other possibilities are that the water was already uncontaminated or that I didn't react to any existing pathogens.) The pre-filter works well for removing larger particles, and the pre-filter adapter is really helpful in that it allows you to invert a bottle during treatment, ensuring the electrodes maintain contact with the water (whereas when I've stirred, I occasional pull it out of the water too far and have to start over).



I have used the SteriPEN Classic 3 on 3 additional nights during long-term testing, as well as about 1/2 dozen day hikes. All testing occurred in the Cascade Mountains and Olympic Peninsula of Washington State. Elevations ranged from sea level to 6,000 ft (1829 m). Temperatures ranged from approximately 28 F (-2 C) to approximately 55 F (13 C).


The SteirPEN Classic 3 has continued to perform well in long-term testing. I have still experienced no illnesses (which, as noted before, could simply be because I hadn't encountered any tainted water), and haven't had any problems with the device.

Since swiitching to the lithium batteries, I have purified at least 35 additional liters of water (I lost exact count), and the lithium batteries are still going strong. I don't yet know how many uses I'll get out of the lithium batteries, but I know I'll use lithium batteries whenever possible in the future for the simple reason that they make the device notably lighter.


The SteriPEN Classic 3 has proven to be an easy-to-use and (apparently) effective water purification system. I find it much more convenient than other treatment systems (pumps and chemical) that I have relied on in the past.


I actually think the SteriPEN Classic 3 has already become my new go-to water purification system. With the exception of those times when I expect to encounter extremely cloudy water (when I'll take a filter), or need to travel ultralight (when I'll use chemical disinfectants), the SteriPEN Classic 3 will be my first choice in water purification. It is so simply and quick, and lighter than my filters, that I see it as my best choice for all-around use.

I would like to thank Hydro-Photon, Inc. and for the opportunity to test the SteriPEN Classic 3. This concludes my report.

This report was created with the Report Writer Version 1. Copyright 2015. All rights reserved.
Read more gear reviews by Mike Curry

Reviews > Water Treatment > Ultraviolet > SteriPEN Classic 3 > Test Report by Mike Curry

Product tested and reviewed in each Formal Test Report has been provided free of charge by the manufacturer to Upon completion of the Test Series the writer is permitted to keep the product. Owner Reviews are based on product owned by the reviewer personally unless otherwise noted.

If you are an avid backpacker, we are always looking for enthusiastic, quality reviewers. Apply here to be a gear tester.

All material on this site is the exclusive property of
BackpackGearTest software copyright David Anderson